/*
 * Copyright (C) 2006 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.internal.telephony.dataconnection;

import android.content.Context;
import android.hardware.radio.V1_0.ApnTypes;
import android.os.PersistableBundle;
import android.telephony.CarrierConfigManager;
import android.telephony.Rlog;
import android.telephony.ServiceState;
import android.text.TextUtils;

import com.android.internal.annotations.VisibleForTesting;
import com.android.internal.telephony.Phone;
import com.android.internal.telephony.PhoneConstants;
import com.android.internal.telephony.RILConstants;
import com.android.internal.telephony.uicc.IccRecords;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Objects;

/**
 * This class represents a apn setting for create PDP link
 */
public class ApnSetting {

    static final String LOG_TAG = "ApnSetting";

    private static final boolean DBG = false;
    private static final boolean VDBG = false;

    static final String V2_FORMAT_REGEX = "^\\[ApnSettingV2\\]\\s*";
    static final String V3_FORMAT_REGEX = "^\\[ApnSettingV3\\]\\s*";

    public final String carrier;
    public final String apn;
    public final String proxy;
    public final String port;
    public final String mmsc;
    public final String mmsProxy;
    public final String mmsPort;
    public final String user;
    public final String password;
    public final int authType;
    public final String[] types;
    public final int typesBitmap;
    public final int id;
    public final String numeric;
    public final String protocol;
    public final String roamingProtocol;
    public final int mtu;

    /**
      * Current status of APN
      * true : enabled APN, false : disabled APN.
      */
    public final boolean carrierEnabled;
    /**
     * Radio Access Technology info
     * To check what values can hold, refer to ServiceState.java.
     * This should be spread to other technologies,
     * but currently only used for LTE(14) and EHRPD(13).
     */
    private final int bearer;
    /**
      * Radio Access Technology info
      * To check what values can hold, refer to ServiceState.java. This is a bitmask of radio
      * technologies in ServiceState.
      * This should be spread to other technologies,
      * but currently only used for LTE(14) and EHRPD(13).
      */
    public final int bearerBitmask;

    /* ID of the profile in the modem */
    public final int profileId;
    public final boolean modemCognitive;
    public final int maxConns;
    public final int waitTime;
    public final int maxConnsTime;

    /**
      * MVNO match type. Possible values:
      *   "spn": Service provider name.
      *   "imsi": IMSI.
      *   "gid": Group identifier level 1.
      */
    public final String mvnoType;
    /**
      * MVNO data. Examples:
      *   "spn": A MOBILE, BEN NL
      *   "imsi": 302720x94, 2060188
      *   "gid": 4E, 33
      */
    public final String mvnoMatchData;

    /**
     * Indicates this APN setting is permanently failed and cannot be
     * retried by the retry manager anymore.
     * */
    public boolean permanentFailed = false;

    public ApnSetting(int id, String numeric, String carrier, String apn,
                      String proxy, String port,
                      String mmsc, String mmsProxy, String mmsPort,
                      String user, String password, int authType, String[] types,
                      String protocol, String roamingProtocol, boolean carrierEnabled, int bearer,
                      int bearerBitmask, int profileId, boolean modemCognitive, int maxConns,
                      int waitTime, int maxConnsTime, int mtu, String mvnoType,
                      String mvnoMatchData) {
        this.id = id;
        this.numeric = numeric;
        this.carrier = carrier;
        this.apn = apn;
        this.proxy = proxy;
        this.port = port;
        this.mmsc = mmsc;
        this.mmsProxy = mmsProxy;
        this.mmsPort = mmsPort;
        this.user = user;
        this.password = password;
        this.authType = authType;
        this.types = new String[types.length];
        int apnBitmap = 0;
        for (int i = 0; i < types.length; i++) {
            this.types[i] = types[i].toLowerCase();
            apnBitmap |= getApnBitmask(this.types[i]);
        }
        this.typesBitmap = apnBitmap;
        this.protocol = protocol;
        this.roamingProtocol = roamingProtocol;
        this.carrierEnabled = carrierEnabled;
        this.bearer = bearer;
        this.bearerBitmask = (bearerBitmask | ServiceState.getBitmaskForTech(bearer));
        this.profileId = profileId;
        this.modemCognitive = modemCognitive;
        this.maxConns = maxConns;
        this.waitTime = waitTime;
        this.maxConnsTime = maxConnsTime;
        this.mtu = mtu;
        this.mvnoType = mvnoType;
        this.mvnoMatchData = mvnoMatchData;

    }

    public ApnSetting(ApnSetting apn) {
        this(apn.id, apn.numeric, apn.carrier, apn.apn, apn.proxy, apn.port, apn.mmsc, apn.mmsProxy,
                apn.mmsPort, apn.user, apn.password, apn.authType, apn.types, apn.protocol,
                apn.roamingProtocol, apn.carrierEnabled, apn.bearer, apn.bearerBitmask,
                apn.profileId, apn.modemCognitive, apn.maxConns, apn.waitTime, apn.maxConnsTime,
                apn.mtu, apn.mvnoType, apn.mvnoMatchData);
    }

    /**
     * Creates an ApnSetting object from a string.
     *
     * @param data the string to read.
     *
     * The string must be in one of two formats (newlines added for clarity,
     * spaces are optional):
     *
     * v1 format:
     *   <carrier>, <apn>, <proxy>, <port>, <user>, <password>, <server>,
     *   <mmsc>, <mmsproxy>, <mmsport>, <mcc>, <mnc>, <authtype>,
     *   <type>[| <type>...],
     *
     * v2 format:
     *   [ApnSettingV2] <carrier>, <apn>, <proxy>, <port>, <user>, <password>, <server>,
     *   <mmsc>, <mmsproxy>, <mmsport>, <mcc>, <mnc>, <authtype>,
     *   <type>[| <type>...], <protocol>, <roaming_protocol>, <carrierEnabled>, <bearerBitmask>,
     *
     * v3 format:
     *   [ApnSettingV3] <carrier>, <apn>, <proxy>, <port>, <user>, <password>, <server>,
     *   <mmsc>, <mmsproxy>, <mmsport>, <mcc>, <mnc>, <authtype>,
     *   <type>[| <type>...], <protocol>, <roaming_protocol>, <carrierEnabled>, <bearerBitmask>,
     *   <profileId>, <modemCognitive>, <maxConns>, <waitTime>, <maxConnsTime>, <mtu>,
     *   <mvnoType>, <mvnoMatchData>
     *
     * Note that the strings generated by toString() do not contain the username
     * and password and thus cannot be read by this method.
     */
    public static ApnSetting fromString(String data) {
        if (data == null) return null;

        int version;
        // matches() operates on the whole string, so append .* to the regex.
        if (data.matches(V3_FORMAT_REGEX + ".*")) {
            version = 3;
            data = data.replaceFirst(V3_FORMAT_REGEX, "");
        } else if (data.matches(V2_FORMAT_REGEX + ".*")) {
            version = 2;
            data = data.replaceFirst(V2_FORMAT_REGEX, "");
        } else {
            version = 1;
        }

        String[] a = data.split("\\s*,\\s*");
        if (a.length < 14) {
            return null;
        }

        int authType;
        try {
            authType = Integer.parseInt(a[12]);
        } catch (NumberFormatException e) {
            authType = 0;
        }

        String[] typeArray;
        String protocol, roamingProtocol;
        boolean carrierEnabled;
        int bearerBitmask = 0;
        int profileId = 0;
        boolean modemCognitive = false;
        int maxConns = 0;
        int waitTime = 0;
        int maxConnsTime = 0;
        int mtu = PhoneConstants.UNSET_MTU;
        String mvnoType = "";
        String mvnoMatchData = "";
        if (version == 1) {
            typeArray = new String[a.length - 13];
            System.arraycopy(a, 13, typeArray, 0, a.length - 13);
            protocol = RILConstants.SETUP_DATA_PROTOCOL_IP;
            roamingProtocol = RILConstants.SETUP_DATA_PROTOCOL_IP;
            carrierEnabled = true;
        } else {
            if (a.length < 18) {
                return null;
            }
            typeArray = a[13].split("\\s*\\|\\s*");
            protocol = a[14];
            roamingProtocol = a[15];
            carrierEnabled = Boolean.parseBoolean(a[16]);

            bearerBitmask = ServiceState.getBitmaskFromString(a[17]);

            if (a.length > 22) {
                modemCognitive = Boolean.parseBoolean(a[19]);
                try {
                    profileId = Integer.parseInt(a[18]);
                    maxConns = Integer.parseInt(a[20]);
                    waitTime = Integer.parseInt(a[21]);
                    maxConnsTime = Integer.parseInt(a[22]);
                } catch (NumberFormatException e) {
                }
            }
            if (a.length > 23) {
                try {
                    mtu = Integer.parseInt(a[23]);
                } catch (NumberFormatException e) {
                }
            }
            if (a.length > 25) {
                mvnoType = a[24];
                mvnoMatchData = a[25];
            }
        }

        return new ApnSetting(-1,a[10]+a[11],a[0],a[1],a[2],a[3],a[7],a[8],
                a[9],a[4],a[5],authType,typeArray,protocol,roamingProtocol,carrierEnabled,0,
                bearerBitmask, profileId, modemCognitive, maxConns, waitTime, maxConnsTime, mtu,
                mvnoType, mvnoMatchData);
    }

    /**
     * Creates an array of ApnSetting objects from a string.
     *
     * @param data the string to read.
     *
     * Builds on top of the same format used by fromString, but allows for multiple entries
     * separated by "; ".
     */
    public static List<ApnSetting> arrayFromString(String data) {
        List<ApnSetting> retVal = new ArrayList<ApnSetting>();
        if (TextUtils.isEmpty(data)) {
            return retVal;
        }
        String[] apnStrings = data.split("\\s*;\\s*");
        for (String apnString : apnStrings) {
            ApnSetting apn = fromString(apnString);
            if (apn != null) {
                retVal.add(apn);
            }
        }
        return retVal;
    }

    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder();
        sb.append("[ApnSettingV3] ")
        .append(carrier)
        .append(", ").append(id)
        .append(", ").append(numeric)
        .append(", ").append(apn)
        .append(", ").append(proxy)
        .append(", ").append(mmsc)
        .append(", ").append(mmsProxy)
        .append(", ").append(mmsPort)
        .append(", ").append(port)
        .append(", ").append(authType).append(", ");
        for (int i = 0; i < types.length; i++) {
            sb.append(types[i]);
            if (i < types.length - 1) {
                sb.append(" | ");
            }
        }
        sb.append(", ").append(protocol);
        sb.append(", ").append(roamingProtocol);
        sb.append(", ").append(carrierEnabled);
        sb.append(", ").append(bearer);
        sb.append(", ").append(bearerBitmask);
        sb.append(", ").append(profileId);
        sb.append(", ").append(modemCognitive);
        sb.append(", ").append(maxConns);
        sb.append(", ").append(waitTime);
        sb.append(", ").append(maxConnsTime);
        sb.append(", ").append(mtu);
        sb.append(", ").append(mvnoType);
        sb.append(", ").append(mvnoMatchData);
        sb.append(", ").append(permanentFailed);
        return sb.toString();
    }

    /**
     * Returns true if there are MVNO params specified.
     */
    public boolean hasMvnoParams() {
        return !TextUtils.isEmpty(mvnoType) && !TextUtils.isEmpty(mvnoMatchData);
    }

    public boolean canHandleType(String type) {
        if (!carrierEnabled) return false;
        boolean wildcardable = true;
        if (PhoneConstants.APN_TYPE_IA.equalsIgnoreCase(type)) wildcardable = false;
        for (String t : types) {
            // DEFAULT handles all, and HIPRI is handled by DEFAULT
            if (t.equalsIgnoreCase(type) ||
                    (wildcardable && t.equalsIgnoreCase(PhoneConstants.APN_TYPE_ALL)) ||
                    (t.equalsIgnoreCase(PhoneConstants.APN_TYPE_DEFAULT) &&
                    type.equalsIgnoreCase(PhoneConstants.APN_TYPE_HIPRI))) {
                return true;
            }
        }
        return false;
    }

    private static boolean imsiMatches(String imsiDB, String imsiSIM) {
        // Note: imsiDB value has digit number or 'x' character for seperating USIM information
        // for MVNO operator. And then digit number is matched at same order and 'x' character
        // could replace by any digit number.
        // ex) if imsiDB inserted '310260x10xxxxxx' for GG Operator,
        //     that means first 6 digits, 8th and 9th digit
        //     should be set in USIM for GG Operator.
        int len = imsiDB.length();
        int idxCompare = 0;

        if (len <= 0) return false;
        if (len > imsiSIM.length()) return false;

        for (int idx=0; idx<len; idx++) {
            char c = imsiDB.charAt(idx);
            if ((c == 'x') || (c == 'X') || (c == imsiSIM.charAt(idx))) {
                continue;
            } else {
                return false;
            }
        }
        return true;
    }

    public static boolean mvnoMatches(IccRecords r, String mvnoType, String mvnoMatchData) {
        if (mvnoType.equalsIgnoreCase("spn")) {
            if ((r.getServiceProviderName() != null) &&
                    r.getServiceProviderName().equalsIgnoreCase(mvnoMatchData)) {
                return true;
            }
        } else if (mvnoType.equalsIgnoreCase("imsi")) {
            String imsiSIM = r.getIMSI();
            if ((imsiSIM != null) && imsiMatches(mvnoMatchData, imsiSIM)) {
                return true;
            }
        } else if (mvnoType.equalsIgnoreCase("gid")) {
            String gid1 = r.getGid1();
            int mvno_match_data_length = mvnoMatchData.length();
            if ((gid1 != null) && (gid1.length() >= mvno_match_data_length) &&
                    gid1.substring(0, mvno_match_data_length).equalsIgnoreCase(mvnoMatchData)) {
                return true;
            }
        }
        return false;
    }

    /**
     * Check if this APN type is metered.
     *
     * @param type The APN type
     * @param phone The phone object
     * @return True if the APN type is metered, otherwise false.
     */
    public static boolean isMeteredApnType(String type, Phone phone) {
        if (phone == null) {
            return true;
        }

        boolean isRoaming = phone.getServiceState().getDataRoaming();
        boolean isIwlan = phone.getServiceState().getRilDataRadioTechnology()
                == ServiceState.RIL_RADIO_TECHNOLOGY_IWLAN;
        int subId = phone.getSubId();

        String carrierConfig;
        // First check if the device is in IWLAN mode. If yes, use the IWLAN metered APN list. Then
        // check if the device is roaming. If yes, use the roaming metered APN list. Otherwise, use
        // the normal metered APN list.
        if (isIwlan) {
            carrierConfig = CarrierConfigManager.KEY_CARRIER_METERED_IWLAN_APN_TYPES_STRINGS;
        } else if (isRoaming) {
            carrierConfig = CarrierConfigManager.KEY_CARRIER_METERED_ROAMING_APN_TYPES_STRINGS;
        } else {
            carrierConfig = CarrierConfigManager.KEY_CARRIER_METERED_APN_TYPES_STRINGS;
        }

        if (DBG) {
            Rlog.d(LOG_TAG, "isMeteredApnType: isRoaming=" + isRoaming + ", isIwlan=" + isIwlan);
        }

        CarrierConfigManager configManager = (CarrierConfigManager)
                phone.getContext().getSystemService(Context.CARRIER_CONFIG_SERVICE);
        if (configManager == null) {
            Rlog.e(LOG_TAG, "Carrier config service is not available");
            return true;
        }

        PersistableBundle b = configManager.getConfigForSubId(subId);
        if (b == null) {
            Rlog.e(LOG_TAG, "Can't get the config. subId = " + subId);
            return true;
        }

        String[] meteredApnTypes = b.getStringArray(carrierConfig);
        if (meteredApnTypes == null) {
            Rlog.e(LOG_TAG, carrierConfig +  " is not available. " + "subId = " + subId);
            return true;
        }

        HashSet<String> meteredApnSet = new HashSet<>(Arrays.asList(meteredApnTypes));
        if (DBG) {
            Rlog.d(LOG_TAG, "For subId = " + subId + ", metered APN types are "
                    + Arrays.toString(meteredApnSet.toArray()));
        }

        // If all types of APN are metered, then this APN setting must be metered.
        if (meteredApnSet.contains(PhoneConstants.APN_TYPE_ALL)) {
            if (DBG) Rlog.d(LOG_TAG, "All APN types are metered.");
            return true;
        }

        if (meteredApnSet.contains(type)) {
            if (DBG) Rlog.d(LOG_TAG, type + " is metered.");
            return true;
        } else if (type.equals(PhoneConstants.APN_TYPE_ALL)) {
            // Assuming no configuration error, if at least one APN type is
            // metered, then this APN setting is metered.
            if (meteredApnSet.size() > 0) {
                if (DBG) Rlog.d(LOG_TAG, "APN_TYPE_ALL APN is metered.");
                return true;
            }
        }

        if (DBG) Rlog.d(LOG_TAG, type + " is not metered.");
        return false;
    }

    /**
     * Check if this APN setting is metered.
     *
     * @param phone The phone object
     * @return True if this APN setting is metered, otherwise false.
     */
    public boolean isMetered(Phone phone) {
        if (phone == null) {
            return true;
        }

        for (String type : types) {
            // If one of the APN type is metered, then this APN setting is metered.
            if (isMeteredApnType(type, phone)) {
                return true;
            }
        }
        return false;
    }

    // TODO - if we have this function we should also have hashCode.
    // Also should handle changes in type order and perhaps case-insensitivity
    @Override
    public boolean equals(Object o) {
        if (o instanceof ApnSetting == false) {
            return false;
        }

        ApnSetting other = (ApnSetting) o;

        return carrier.equals(other.carrier)
                && id == other.id
                && numeric.equals(other.numeric)
                && apn.equals(other.apn)
                && proxy.equals(other.proxy)
                && mmsc.equals(other.mmsc)
                && mmsProxy.equals(other.mmsProxy)
                && TextUtils.equals(mmsPort, other.mmsPort)
                && port.equals(other.port)
                && TextUtils.equals(user, other.user)
                && TextUtils.equals(password, other.password)
                && authType == other.authType
                && Arrays.deepEquals(types, other.types)
                && typesBitmap == other.typesBitmap
                && protocol.equals(other.protocol)
                && roamingProtocol.equals(other.roamingProtocol)
                && carrierEnabled == other.carrierEnabled
                && bearer == other.bearer
                && bearerBitmask == other.bearerBitmask
                && profileId == other.profileId
                && modemCognitive == other.modemCognitive
                && maxConns == other.maxConns
                && waitTime == other.waitTime
                && maxConnsTime == other.maxConnsTime
                && mtu == other.mtu
                && mvnoType.equals(other.mvnoType)
                && mvnoMatchData.equals(other.mvnoMatchData);
    }

    /**
     * Compare two APN settings
     *
     * Note: This method does not compare 'id', 'bearer', 'bearerBitmask'. We only use this for
     * determining if tearing a data call is needed when conditions change. See
     * cleanUpConnectionsOnUpdatedApns in DcTracker.
     *
     * @param o the other object to compare
     * @param isDataRoaming True if the device is on data roaming
     * @return True if the two APN settings are same
     */
    @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE)
    public boolean equals(Object o, boolean isDataRoaming) {
        if (!(o instanceof ApnSetting)) {
            return false;
        }

        ApnSetting other = (ApnSetting) o;

        return carrier.equals(other.carrier)
                && numeric.equals(other.numeric)
                && apn.equals(other.apn)
                && proxy.equals(other.proxy)
                && mmsc.equals(other.mmsc)
                && mmsProxy.equals(other.mmsProxy)
                && TextUtils.equals(mmsPort, other.mmsPort)
                && port.equals(other.port)
                && TextUtils.equals(user, other.user)
                && TextUtils.equals(password, other.password)
                && authType == other.authType
                && Arrays.deepEquals(types, other.types)
                && typesBitmap == other.typesBitmap
                && (isDataRoaming || protocol.equals(other.protocol))
                && (!isDataRoaming || roamingProtocol.equals(other.roamingProtocol))
                && carrierEnabled == other.carrierEnabled
                && profileId == other.profileId
                && modemCognitive == other.modemCognitive
                && maxConns == other.maxConns
                && waitTime == other.waitTime
                && maxConnsTime == other.maxConnsTime
                && mtu == other.mtu
                && mvnoType.equals(other.mvnoType)
                && mvnoMatchData.equals(other.mvnoMatchData);
    }

    /**
     * Check if neither mention DUN and are substantially similar
     *
     * @param other The other APN settings to compare
     * @return True if two APN settings are similar
     */
    public boolean similar(ApnSetting other) {
        return (!this.canHandleType(PhoneConstants.APN_TYPE_DUN)
                && !other.canHandleType(PhoneConstants.APN_TYPE_DUN)
                && Objects.equals(this.apn, other.apn)
                && !typeSameAny(this, other)
                && xorEquals(this.proxy, other.proxy)
                && xorEquals(this.port, other.port)
                && xorEquals(this.protocol, other.protocol)
                && xorEquals(this.roamingProtocol, other.roamingProtocol)
                && this.carrierEnabled == other.carrierEnabled
                && this.bearerBitmask == other.bearerBitmask
                && this.profileId == other.profileId
                && Objects.equals(this.mvnoType, other.mvnoType)
                && Objects.equals(this.mvnoMatchData, other.mvnoMatchData)
                && xorEquals(this.mmsc, other.mmsc)
                && xorEquals(this.mmsProxy, other.mmsProxy)
                && xorEquals(this.mmsPort, other.mmsPort));
    }

    // check whether the types of two APN same (even only one type of each APN is same)
    private boolean typeSameAny(ApnSetting first, ApnSetting second) {
        if (VDBG) {
            StringBuilder apnType1 = new StringBuilder(first.apn + ": ");
            for (int index1 = 0; index1 < first.types.length; index1++) {
                apnType1.append(first.types[index1]);
                apnType1.append(",");
            }

            StringBuilder apnType2 = new StringBuilder(second.apn + ": ");
            for (int index1 = 0; index1 < second.types.length; index1++) {
                apnType2.append(second.types[index1]);
                apnType2.append(",");
            }
            Rlog.d(LOG_TAG, "APN1: is " + apnType1);
            Rlog.d(LOG_TAG, "APN2: is " + apnType2);
        }

        for (int index1 = 0; index1 < first.types.length; index1++) {
            for (int index2 = 0; index2 < second.types.length; index2++) {
                if (first.types[index1].equals(PhoneConstants.APN_TYPE_ALL)
                        || second.types[index2].equals(PhoneConstants.APN_TYPE_ALL)
                        || first.types[index1].equals(second.types[index2])) {
                    if (VDBG) Rlog.d(LOG_TAG, "typeSameAny: return true");
                    return true;
                }
            }
        }

        if (VDBG) Rlog.d(LOG_TAG, "typeSameAny: return false");
        return false;
    }

    // equal or one is not specified
    private boolean xorEquals(String first, String second) {
        return (Objects.equals(first, second)
                || TextUtils.isEmpty(first)
                || TextUtils.isEmpty(second));
    }

    // Helper function to convert APN string into a 32-bit bitmask.
    private static int getApnBitmask(String apn) {
        switch (apn) {
            case PhoneConstants.APN_TYPE_DEFAULT: return ApnTypes.DEFAULT;
            case PhoneConstants.APN_TYPE_MMS: return ApnTypes.MMS;
            case PhoneConstants.APN_TYPE_SUPL: return ApnTypes.SUPL;
            case PhoneConstants.APN_TYPE_DUN: return ApnTypes.DUN;
            case PhoneConstants.APN_TYPE_HIPRI: return ApnTypes.HIPRI;
            case PhoneConstants.APN_TYPE_FOTA: return ApnTypes.FOTA;
            case PhoneConstants.APN_TYPE_IMS: return ApnTypes.IMS;
            case PhoneConstants.APN_TYPE_CBS: return ApnTypes.CBS;
            case PhoneConstants.APN_TYPE_IA: return ApnTypes.IA;
            case PhoneConstants.APN_TYPE_EMERGENCY: return ApnTypes.EMERGENCY;
            case PhoneConstants.APN_TYPE_ALL: return ApnTypes.ALL;
            default: return ApnTypes.NONE;
        }
    }
}
